Zwelakhe Mnguni, Chief Investment Officer at Benguela Global Fund Manager, a Shoprite investor, who is opposed to Steinhoff taking a controlling stake in Africa’s largest retailer tells CNBC Africa why Steinhoff’s board must step down.Zwelakhe Mnguni, Chief Investment Officer at Benguela Global Fund Manager, a Shoprite investor, who is opposed to Steinhoff taking a controlling stake in Africa’s largest retailer tells CNBC Africa why Steinhoff’s board must step down.